Crystals- Crystals are a solid material made of ions, atoms and molecules that are arranged in a repeating pattern to become solid.
Atoms, ions and molecules that form minerals are present in the space in a tidy way and according to well-defined geometrical shapes, which are called crystal lattices. The structure of the crystal lattice defines the shape of the crystal as we see it.
Rocks- Rocks are a natural material, hard or soft, consisting of one or more minerals.
Stones- Stones are a solid, non-metallic mineral matter. Stones form together to make a Rock. One of the main differences is that Stones are always hard while a Rock can be hard or soft. Both are formed from different minerals.
Minerals- Minerals are solid substances present in nature and can be made of one element or elements combined together. Gold, Silver and carbon are examples of elements that form minerals on their own.
Information gathered from:
http://www.eniscuola.net/en/argomento/subsoil/rocks-and-minerals/what-are-minerals/
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